Post No. 17: Time

Time is a very strange thing. Although we know it progresses in regular intervals of seconds, minutes and hours, we experience it very differently.  For example, when we are engrossed in something, time seems to fly.  If we are impatiently waiting for a bus or a latecomer to arrive, time crawls.  My English mother used to tell  me this saying if I complained about the time, “when I was a child time crept; when I was young time strolled; when I was an adult time ran, and when I was old time flew.”  It wasn’t until later I discovered she stole this saying from an inscription on a clock in Chester Cathedral.

The nature of time turned out to be one of the key features of Einstein’s special relativity theory and general relativity theory.  In special relativity, Einstein made the assumption that the speed of light was the same no matter one’s reference point.  So if you are watching a rocketship travelling near the speed of light and the astronaut aboard shines a flashlight, you will both see the light traveling at the same speed. If you do the relatively simple math, it turns out that time is experienced differently by both parties, and the astronaut ages more slowly.  In general relativity, Einstein made another basic assumption that gravity and acceleration were equivalent. It took him a couple years with the help of colleagues from his old university days to correctly work out the very complicated math.  The tensor math that was crucial to his equations was only developed a decade or so beforehand, and Riemann Geometry about sixty years before.  The results made Einstein famous after Sir Arthur Eddington, an English astronomer, confirmed his theory by measuring, during a solar eclipse, the deflection of light waves from distant stars traveling close to the sun. His results precisely matched the deflection predicted by Einstein’s math.  It was the year 1919 and overnight Einstein became a celebrity throughout the world.  What is most remarkable arising out of Einstein’s math is that all of space is actually a “space-time fabric” woven by three dimensional matter and time.  Time and spatial dimensions follow a curved path around massive objects like the earth and sun.  For example, general relativity must be accounted for to precisely calculate the orbits of satellites around the earth.  If not for this your GPS directions would be inaccurate.  Time slows down near massive objects.  For example, according to general relativity if you are living at sea level, you age minutely less than someone living on the international space station due to the fact you are closer to a massive object, the earth.  (But special relativity reverses this effect due to the space station’s incredible velocity.)

The implications of both general relativity and quantum physics have led to some very interesting and startling theories about the nature of time and space.  General relativity leads to a theory of a “block universe” where every event in space and time has already occurred.  Quantum physicists have suggested the theory of a “multiverse” to account for all the possible probabilities of photons existing as either a wave or a particle. Both general relativity and quantum physics have resulted in some fantastic real world applications, yet the implications of these theories about time have not been proven.  In the meantime they have given us some really cool science fiction!

Ok, enough science.  The reader can see that time is not only relative to how we experience it, but in the cosmos, time is relative to one’s velocity and location. The unproven theories will remain in the realm of science fiction, at least for now.

Let’s return to the issue of how we as humans experience time.  Time seems to flow for us from past to future, and this flow can seem either fast or slow at different times for us. We also have the ability to time travel in our minds.  Our mental time travel simply means that we can imagine the past and speculate on the future in our minds. Yet I am sure every reader would agree that while they are imagining the past or future, they are physically right here, right now.  It is impossible to be anywhere but right here, right now every moment of your life, except in science fiction.

As I have subtly alluded to in previous posts (See posts 11 and 12), this mental time travel is possible because we can create constructs in mind about everything, including past, present, future, time, self, and on and on.  Yet one can understand intellectually that one can exist only right here, right now.  One can experience this “all is now” viscerally if the mind quiets sufficiently enough.  I may explore more about this latter phenomenon in a future post.

One of the reasons I became very interested in “Gifts from Greeks“ (Post No.16) is that the ancient Greeks developed a practical way of living based on “right here, right now”.  The next post will explore further the wisdom of ancient Greece, and will provide my own synthesized take away from the Stoics and Epicureans.  Stay tuned.